.header{
    width: 100%;
    height: 80px;
    background: white;

}
.display-bth{
    top: 18px;
    right: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 20px;
    width: 80px;
    height: 40px;
    cursor: pointer;
    background: lightskyblue;
    position: absolute;
    border-radius: 10px;
    transition: 0.3s;

}  
.display-bth:hover{
    background: black;
    color:white ;
}
input[type='checkbox']{
    display: none;
}    
#display:checked~.container{
    display: block;
}
.container{
    display: none;
    top:50%;
    left:50%;
    transform: translate(-50%,-50%);
    background: whitesmoke;
    width: 350px;
    height: 400px;
    padding: 30px;
    position: absolute;
    border-radius: 15px;
    opacity: 70%;
}
.close-bth{
    right: 10%;
    position: absolute;
    color: black;
    font-size: 30px;
    cursor: pointer;
    font-weight: bold;
    background: none;
    transition: 0.2s;
}
.close-bth:hover{
    color: red;

}
h1{
    background: none;
    text-align: center;
    margin: 10px 0;
    color: black;
    /*text transform的话中文就不需要
    /*text transform：uppercase;*/
}
form{
    background: none;

}
label{
    background: none;
    color: black;
    font-weight: bold;
    font-size: 20px;
   
}
input{
    background: none;
    display: block;
    width: 90%;
    font-size: 20px;
    border: none;
    outline: none;
    border-bottom: 2px solid black;
    padding: 10px;
}
.button{
    display: block;
    margin-top: 20px;
    width: 95%;
    color: white;
    cursor: pointer;
    font-weight: bold;
    font-size: 20px;
    border-radius: 10px;
    background: black;
    border: none;
    outline: none;
    padding: 10px;
    transition: 0.3s;

}
.button:hover{
    background:lightseagreen;
}
form a{
    font-weight: bold;
    color: lightseagreen;
    background: none;
    text-decoration: none;
    transition: 0.2s;
}
form a:hover{
    color: rgb(13,84,81);
}
.forgot{
    background: none;
    text-align: center;
    margin: 40px 5px;
    color: black;
}
